Friday, July 10, 2015

Summary of 2014 Bobcat Observations in Ohio

Bobcat at Columbus Zoo

Division of Wildlife

Ohio
Department of Natural Resources

Waterloo
Wildlife Research Station

Athens,
OH 45701 15

June
2015

Summary of 2014 Bobcat Observations in Ohio

Bobcats were found throughout Ohio in early settlement times. They were concentrated
primarily in the large, lowland areas of the north and unglaciated Allegheny
Plateau region of the southeastern portion of the state. As swamps and lowlands
were drained and forests cleared to make way for settlements and cropland, the
bobcat population declined. By 1850, they were considered extirpated from the
state. From 1850 through the 1960s, there were occasional reports of bobcats,
mainly in eastern Ohio. From 1970 through 2014, there have been 1,195 verified
(e.g., positive identification via roadkill, incidental trappings, etc.)
reports of bobcats in Ohio. The bobcat was removed from the Ohio Endangered and
Threatened Species List in July 2014, but remains protected (no harvest
season). In 1997, a project was initiated by the Division of Wildlife to
systematically monitor the status of bobcats in Ohio.

Unverified reports – A total of 2,349 unverified bobcat sightings was
received from 1970-2014; the annual number of which has been declining over the
past several years: 176 in 2014, 226 in 2013, and 242 unverified reports in
2012. Unverified sightings were reported from 54 counties during 2014 and from
86 counties since 1970 (Fig. 1). Unverified reports in 2014 were obtained
primarily through Call Center (n = 63; 36%).

Verified reports – Verified reports represent positive identification of
a bobcat, usually as a result of the animal being killed on the road,
photographed, or incidentally trapped. Verified reports provide the best
information regarding the distribution and abundance of bobcats in Ohio.
Further, they provide an important index of change in annual relative
abundance. Since 1970, there have been 1,195 verified reports of bobcats in
Ohio, of which the great majority have occurred since 2000 (n = 1,167; 98%).
There were 197 verified bobcat reports in 2014, similar to that of the previous
year (n = 200). These 197 reports included 110 trail camera pictures or videos,
43 roadkills, 16 incidentally trapped bobcats, 15 photographs, 12 sightings by
Ohio Department of Natural Resources staff or other qualified personnel, and 1
observation of tracks. Verified bobcat reports were documented in 39 counties
during 2014 and in 58 counties since 1970 (Fig. 2). Bobcat sightings during
2014 continue to be highly aggregated. Of the 197 verified reports, 22 (11%)
were from Noble County, and 97 (49%) were reported within a 1-county radius of
Noble County.

Overall, verified sightings have increased steadily over the past
decade, only decreasing in apparent growth over the past year (Fig. 3). Bobcat mortality,
particularly vehicle-related, has historically been the primary source of
verified sightings. Prior to 2006, trail cameras photos were a negligible
source of sightings. Since that time, however, the number of sightings via
trail camera photos has increased dramatically. In 2008, trail camera
photographs became the primary source. Other sources of verified sightings,
although generally increasing over time, have not shown the same rapid increase
(Fig. 4). It is likely that the growing popularity of trail cameras, as well as
the decline in their cost, is largely responsible for the increase in the
receipt of trail camera photos of bobcats. As such, this source of data is
biased and should be interpreted with caution.

The decline in the number of unverified sightings over the past several
years and the stabilization of verified sightings over the past 2 years is
likely due in part to decreased interest in reporting sightings given the
bobcat’s change in status to threatened and subsequent delisting. Given the
numerous confounding factors involved in the use of sighting data as an index
to relative abundance, a new method of tracking bobcat abundance (e.g., track
stations, camera stations, etc.) should be implemented and initial data
obtained before a trapping season is implemented.

We thank Division of Wildlife personnel who were involved in
investigating and reporting observations.